Sean Abbott has helped power holders Surrey towards another triumph while Cameron Bancroft hit a superb century on a day when Australians shone again in a sun-baked county championship program.
Surrey are looking well set in their title defence as they need just 58 runs on the final day, with all 10 wickets still standing, to record a third straight division one victory, thanks in part to fine contributions from the returning Abbott and the evergreen Dan Worrall.
West Indian Kemar Roach may have been the star of the day at The Oval on Sunday, taking 6-46 as the visitors were bowled out for 209 in their second innings but Abbott, back in London after not making Australia's T20 World Cup squad, was in sparkling form with bat and ball in his first red-ball match in nearly a year.
Last season, the NSW allrounder became an Oval favourite, taking 37 first-class scalps in nine matches as well as smashing an unforgettable 41-ball unbeaten 110no in a T20 match.
He looked in the mood to carry on where he left off, coming in at No.10 and cracking an unbeaten 50 off 58 balls to help provide late-innings support to Jamie Smith, whose brilliant 155 did most to give Surrey a significant first-innings lead.
The pair put on 115 in just over 18 overs for the ninth wicket that hauled Surrey up to 464 all out in reply to Warwickshire's 343.
Then, while Roach did most of the damage, Abbott, who also took two wickets in the first innings, chipped in with the key dismissal of Ed Barnard, who'd made 44 in a stubborn 75-run stand with Sam Hain, pulling off a stunning caught-and-bowled.
Anglo-Aussie Worrall, one of Surrey's spearheads again this season as he was in their previous two championship triumph, finally got his reward after beating the bat regularly, taking the final wicket of the innings. He finished with 1-53 off his 15 overs, while Abbott took 1-32 off 11.
Surrey openers Rory Burns and Dom Sibley then took them close to victory at 0-31 by stumps.
At Northampton's Wantage Road, Bancroft, who had scored 53 in the first innings, ended up 130 not out in Gloucestershire's second knock against Northants to steer his side into position for a final-day victory push.
It was the Australian Test opener's first ton in his second stint with the West Country county, enabling them to declare on 5-319 with a huge lead of 557. Northants were battling, though, reaching 2-144 by the close.
Bancroft's 130no was his 27th first-class hundred and was compiled off 205 balls, with 11 fours and a six.
Without the rested Nathan Lyon, Lancashire took a pounding from Nottinghamshire captain Haseeb Hameed, who hit a record-breaking, career-best 247no at Trent Bridge in their first-innings 501 to help his side take control.
Hameed's score is the highest by a Nottinghamshire player carrying his bat through an innings in the county's history.